Great question — answering as the UphillTech team:
IBM WebSphere Commerce The application is IBM WebSphere Commerce , a Java based application. Very powerful application, but obviously for enterprise companies, so that means your customer must be ready to shell out some big bucks. I'm not sure if you can offer this directly to your customer though, or if you need to become an IBM certified partner. It offers call center, sales center and complete warehouse distribution control; amazing software. We use the application - has multi store, multi language and multi development team country office based systems. It starts around £100,000 Updated You asked about justifying the software. I don't wish to sound rude but this major eCommerce software...
Full answer by TheBlackBenzKid: https://stackoverflow.stackexchange.com/a/12282843 (CC BY-SA 4.0).
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